Also aside from Rail Head Treatment Trains what else are they predominantly used for?

Where are they based and are they all based at the same place?

Are there any stored or scrapped?

Thanks in advance
Chris

If your talking about the Windhoff MPVs, None of them are scrapped. As for where they are based, mostly out of Eastleigh Works & Epsom Depot, and their main purposes under Network Rail are Weedkilling duties in the summer, and RHTT duties in the Autumn & Winter.

Don't know if you've read the Wiki page about them, but there's some usefull info on there. (Would try and answer a few more of your questions but i've got to head out to work in 5).

There are thirty two Windhoff MPV sets that are utilised on rail head treatment trains and other similar duties. They operate as "master and slave" pairs. They are also used on weedkilling trains during the spring, as the units that they carry on the flatbed section behind the cab are modular and can be swapped to suit whichever role they are required to perform.

None of the thirty two MPV pairs that were ordered by Railtrack have been scrapped. However there are other MPV units that were built specifically for the West Coast route modernisation and are fitted with either piling equipment or overhead line renewal equipment, many of which are presently stored at York.

There are 32 Network Rail Windhoff Master & Slave units in operation. They are 98901-32 (Master units) & 98951- 98982 (Slave units). They work in semi permanent pairings so 98901 will work with 98951 etc.

They are used for RHTT works, both water canon & sandite, weed killing on the track side and on embankments, de icing and winter treatment works. Modules on the flat bed section of the vehicles are changed according to duty. Here is an example: http://www.flickr.com/photos/bolckow/7030129811/

They are based at various location around the country. York Holgate, Slateford, Rutherglen, Inverness, Wigan, Tonbridge, Eastleigh, Horsham, Effingham and some other places I have forgotten!